Re-shapeable medical device

ABSTRACT

A medical device enables a user to bend it into a shape to suit a specific patient need or to orient efficiently the medical device for use. The medical device includes an elongate member, a mechanism, and an actuator. The mechanism is disposed at the distal portion of the elongate member. The actuator is at least partially disposed within the elongate member and coupled to the mechanism for actuating the mechanism relative to the elongate member. The elongate member is capable of being bent into a shape by the user and of retaining the shape during use. The shape may include multiple bends, in multiple directions, as needed for an application. Thereafter, the elongate member is capable of being bent into a second shape by the user and of maintaining the second shape during use.

RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.10/384,682, filed on Mar. 10, 2003, the contents of which are hereinincorporated by reference in its entirety.

TECHNICAL FIELD

The invention relates to devices and methods for accessing remote areaswithin the body and performing surgical procedures therein.

BACKGROUND INFORMATION

For many surgical procedures, it is necessary to make a large opening inthe human body to expose the area that requires surgical repair. Thereare instruments available that allow for viewing certain areas of thehuman body through, for example, a natural body opening or a smallpuncture wound, and thus avoid the need for making such large openings.These instruments, called endoscopes, can be used in conjunction withspecialized surgical instruments to detect, diagnose, sample, and repairareas of the body that previously required open surgery to access.

Some surgical instruments used in endoscopic procedures are limited bythe way they grasp tissue, cut tissue, apply a suture, or recapture theneedle and suture. Furthermore, many surgical instruments arecomplicated and expensive to use due to the numerous parts and/orsubassemblies required to make them function properly. Suturing, inparticular, remains a delicate and time-consuming aspect of mostsurgeries, including those performed endoscopically.

In addition, many of the instruments used in endoscopic procedures arelimited by the manner in which they access the areas of the human bodyin need of diagnosis, sampling, treatment, or repair. In particular, theinstruments may not be able to access tissue or organs that are locateddeep within the body or that are in some way obstructed. The instrumentsused in endoscopic procedures typically have a rigid shaft, and do notallow the user to contour the shaft for a more efficient orientation toreach the location of diagnosis, sampling, treatment, or repair.Instruments with various shaft configurations have been introduced toaccommodate specific applications. Thus, a user's inventory ofinstruments may include a number of rigid shaft instruments for variousapplications.

SUMMARY OF THE INVENTION

The invention generally relates to a medical device for performing asurgical procedure, such as removing a mass of tissue, grasping a massof tissue, or passing a suture through tissue. Specifically, in oneembodiment, the invention is directed to a medical device that can bebent by a user into a shape to suit a specific patient need or toefficiently orient the distal portion of the device to reach thelocation of use. The shape may include multiple bends, in multipledirections, as needed for a particular application. The medical devicemaintains the shape during use. Thereafter, the medical device iscapable of being bent into a second shape by the user to suit anotherspecific patient need or to efficiently orient the distal portion of thedevice to reach the location of another use; the device is furthercapable of maintaining the second shape during use.

In one aspect, the invention is directed to a medical device includingan elongate member, a mechanism, and an actuator. The elongate member iscapable of being bent into a shape by a user and of retaining the shapeduring use. The mechanism is an arrangement of one or more partsconnected and/or operated to perform a task, such as diagnosis,sampling, treatment, or repair. The mechanism is disposed at a distalportion of the elongate member. The actuator is at least partiallydisposed within the elongate member and coupled to the mechanism foractuating the mechanism relative to the elongate member.

In another aspect, the invention relates to a medical device includingan elongate member, an adapter, and an actuator. The elongate member iscapable of being bent into a shape by a user and of retaining the shapeduring use. The adapter is disposed at a distal portion of the elongatemember for coupling to a mechanism. The actuator is at least partiallydisposed within the elongate member and is capable of coupling to themechanism and of actuating the mechanism.

In yet another aspect, the invention relates to a suturing instrumentincluding an elongate member, a head, a needle carrier, and an actuator.The elongate member is capable of being bent into a shape by a user andof retaining the shape during use. The head extends from the distalportion of the elongate member. The needle carrier is disposed withinthe head. The actuator is at least partially disposed within theelongate member. The actuator is also coupled to the needle carrier foradvancing the needle carrier out of the head. In one embodiment, thehead defines an opening, the needle carrier holds a needle, and theactuator advances the needle carrier out of the opening. In addition,the head may include a needle catch having at least one opening forreceiving the needle.

In various embodiments of the foregoing aspects of the invention, theelongate member may have a variable stiffness along its length. Thediameter of the elongate member may vary along its longitudinal axis.For example, the elongate member may have a smaller diameter at itsdistal end than at its proximal end. Further, the elongate member may bea tube. The tube may have a non-uniform wall-thickness. The non-uniformwall-thickness may be at least partially due to scoring, which may bedone in a spiral pattern.

In additional embodiments, the elongate member may be made of metals,alloys and plastics. The metals may be selected from nickel, copper,stainless steel, cobalt, vanadium, chromium, iron, and superelasticmetallic alloys. The plastics may be selected from synthetic plastics,polyurethanes, polyester elastomers, and nylons. The external surface ofthe elongate member may be at least partially covered with abiocompatible material. The biocompatible material may be stainlesssteel, polyvinyl chloride, polytetraflouroethylene, expandedpolytetraflouroethylene, ethylene-tetrafluoroethylene, silicone, orcombinations thereof.

In some embodiments of the foregoing aspects of the invention, themechanism associated with the medical device is an imaging device, astapling device, a biopsy device, an injection device, a cutting deviceor a capturing device. The adapter is adjustable relative to theelongate member. Adjustable, in these embodiments, means articulableand/or rotatable with respect to the elongate member.

In some embodiments of the foregoing aspects of the invention, themedical device is a suturing instrument. In one such embodiment, thedistal portion of the elongate member defines an opening, the mechanismis a needle carrier for holding a needle, and the actuator advances theneedle carrier out of the opening. In another such embodiment, themechanism is a suturing head that extends from the adapter and definesan opening, a needle carrier for holding a needle is disposed within thehead, and the actuator advances the needle carrier out of the opening.The suturing instrument may also include a needle catch disposedproximate the distal portion of the elongate member. The needle catchmay include at least one opening for receiving the needle. In someembodiments of the suturing instrument, the head is adjustable withrespect to the elongate member. Adjustable, in such an embodiment, meansarticulable and/or rotatable with respect to the elongate member.

In some embodiments of the foregoing aspects of the invention, theelongate member is capable of being bent into a second shape by the userand of retaining the second shape during use. In other embodiments, theelongate member is capable of being bent into a shape that includes oneor more bends. In yet another embodiment, the elongate member is capableof bending in one or more directions.

Advantages and features of the invention disclosed herein will becomeapparent through reference to the following description, theaccompanying drawings, and the claims. Furthermore, it is to beunderstood that the features of the various embodiments described hereinare not mutually exclusive and can exist in various combinations andpermutations.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like reference characters generally refer to the sameparts throughout the different views. Also, the drawings are notnecessarily to scale, emphasis instead generally being placed uponillustrating the principles of the invention. In the followingdescription, various embodiments of the present invention are describedwith reference to the following drawings, in which:

FIG. 1A is a schematic plan view of one embodiment of a medical devicein accordance with the invention;

FIGS. 1B and 1C are schematic cross-sectional views of the proximal anddistal portions of the medical device of FIG. 1A;

FIG. 2A is a schematic plan view of a needle coupled to a suture for usein a suturing instrument in accordance with the invention;

FIG. 2B is a schematic perspective view of a needle catch for use withthe suturing instrument of FIG. 1A;

FIG. 3 is a schematic view of a portion of an alternative actuator foruse in a medical device in accordance with the invention;

FIG. 4A is a partial schematic cross-sectional view of anotherembodiment of a medical device in accordance with the invention;

FIG. 4B is a schematic plan view of the medical device of FIG. 4A bentinto a more efficient shape for a particular application; and

FIGS. 5A and 5B are schematic perspective views of an exemplary elongatemember bent into a first and a second shape, respectively.

DESCRIPTION

Embodiments of the invention are described below. It is, however,expressly noted that the invention is not limited to these embodiments,but rather the intention is that variations, modifications, andequivalents are included.

In accordance with one illustrative embodiment of the invention, FIG. 1Adepicts a medical device 100 including an elongate member 104, aproximal portion 108, and a distal portion 106. The elongate member 104is capable of being bent into a shape and of retaining the shape duringuse. The elongate member 104 enables a user to bend the device 100 intoa shape to suit a specific patient need or to efficiently orient thedistal portion of the device 100 to reach the location of use. The shapemay include multiple bends, in multiple directions, as needed for aparticular application. The device 100 maintains the shape during use.Thereafter, the elongate member 104 is capable of being bent into asecond shape to suit another specific patient need or to efficientlyorient the distal portion of the device 100 to reach the location ofanother use; the device 100 is further capable of maintaining the secondshape during use. The elongate member 104 is not limited to two shapesand can be repeatedly bent into essentially any number of shapes, asnecessary.

In the illustrative embodiment of FIG. 1A, the medical device 100 alsoincludes an adapter 114 (shown in FIG. 1C) and an actuator 110. Theadapter 114 is disposed at the distal portion of the elongate member 104and is capable of coupling to a mechanism. The actuator is at leastpartially disposed within the elongate member 104 and is capable ofcoupling to the mechanism and actuating the mechanism. In the particularillustrative embodiment of FIG. 1A, the mechanism is a suturing head 109and the medical device 100 is, therefore, a suturing instrument.Accordingly, the medical device is used for suture placement. In otherembodiments, the mechanism may be an imaging device, a stapling device,a biopsy device, an injection device, a cutting device, or a capturingdevice.

The elongate member 104, in the depicted embodiment, is mechanicallycoupled to a handle 102 at the proximal portion 108. The handle 102 maytake a variety of forms in various embodiments. For example, the handle102 may be one of the types used with Boston Scientific Corporationsuturing systems, in particular the Capio® Push & Catch suturing system.

The adapter 114, in the depicted embodiment, mechanically couples thedistal portion of the elongate member 104 to head 109. The medicaldevice 100 may be used with a variety of heads to suit a particularapplication. Examples of different types of heads are found in U.S. Pat.Nos. 6,096,051 and 6,296,608, and U.S. patent application Ser. Nos.10/210,984 and 60/388,458, each of which is hereby incorporated byreference in its entirety. These types of heads can include forceps, asnare, a pair of scissors, a knife, a suturing tool, a needle, or anyother mechanism, such as those previously described. Additionally,either the head 109 or the adapter 114 may be articulable or rotatablerelative to the elongate member 104. For example, the adapter 114 andhead may rotate about a longitudinal axis 190.

In the illustrative embodiment depicted in FIG. 1A, the actuator 110extends longitudinally through the elongate member 104 to the distalportion 106 of the suturing instrument 100, where the actuator 110 iscoupled to a needle carrier 124 (FIG. 1C) within the head 109. Theactuator I IO enables the needle carrier 124 to move a needle 128 (FIG.2A) between a retracted position and a deployed position. In the aspectof the invention depicted in FIG. 1A, the needle carrier 124 is disposedwithin the head 109 extending from the adapter 114 disposed at thedistal portion 106 of the elongate member 104. The actuator 110 andneedle carrier 124 are shown in detail in FIGS. 1B and 1C.

Referring to the illustrative embodiment of the invention depicted inFIG. 1B, the proximal portion 108 of the medical device 100 includes thehandle 102, the elongate member 104, and part of the actuator 110. Asuture clip 144 may be coupled to the handle 102 or the elongate member104 to hold an end of one or more sutures prior to placement in apatient.

In the illustrative embodiment depicted in FIG. 1B, the proximal portionof the actuator 110 includes a button 117 and a shaft 116 (together112), a bearing 118, a hole 121, a button end 119, and a wireform 103.The bearing 118 rides along a surface 105 that is formed by the insideof the elongate member 104. A wireform 103 is inserted into the hole121, coupling it to the actuator button 117. A spring 115 encircles thewireform 103, abuts the button end 119, and is compressed between thebutton end 19 and a spring washer 113.

The distal portion of the actuator 110 depicted in FIG. 1B includes thespring washer 113, a center tube 107, a pusher wire 111, and a guidancesleeve 109. The spring washer 113 is seated upon the center tube 107.The center tube 107 is housed by the surface 105 and is constrained inthe distal portion 106 of the medical device 100. The pusher wire 111 isattached to the wireform 103 by means of a weld, a crimp, a coupling,adhesive, or other means, and is slidably disposed within the guidancesleeve 109, the sleeve 109 being disposed within a surface 123 formed bythe inside diameter of the center tube 107. In one embodiment, thepusher wire 111 is constructed of a shape memory material, such asnitinol. Nitinol is a nickel-titanium alloy. Preferably, the shapememory material is chosen for its combination of properties that allowfor bendability and high column strength when constrained.

Referring to the illustrative embodiment of the invention depicted inFIG. 1C, the distal portion 106 of the medical device 100 of FIG. 1Aincludes the elongate member 104 and a portion of the actuator 110coupled to the mechanism, in the form of the head 109. The portion ofthe actuator 110 depicted in FIG. 1C includes the pusher wire 111, abackstop washer 156, a pocket 160 that includes a back wall 162, acoupling 150, a track 152, a downstop washer 158, a pocket 164 thatincludes a wall 166, and a carrier wire 154. The pusher wire 111 of theactuator 110 is attached by welding or other means to the coupling 150,which is slidably disposed within the track 152. The coupling 150 isattached to the carrier wire 154, which by virtue of its attachment tothe coupling 150 is also slidably disposed within the track 152. Thecarrier wire 154 is mechanically coupled to the extendable needlecarrier 124 by means of a weld, a coupling, adhesives, or other means.The coupling 150 abuts the backstop washer 156 that is slidably disposedabout the pusher wire 111 and is contained within the pocket 160 thatincludes the back wall 162, against which the backstop washer 156 rests.The track 152 terminates distally in the pocket 164 that includes thewall 166. The downstop washer 158 is slidably disposed about the carrierwire 154 and constrained within the pocket 164.

In some illustrative embodiments, such as depicted in FIG. 1C, themedical device 100 includes an adapter 114 that couples the distalportion of the elongate member 104 to a mechanism (for example, the head109 in FIG. 1C). In one embodiment, the adapter 114 includes anarticulation device. The articulation device facilitates the rotation(in the directions indicated by arrow 182) and positioning of themechanism. The articulation device may, in conjunction with the shape ofthe elongate member 104 established by the user, facilitate access todeep and/or difficult to reach areas within the patient. The adapter 114may also be fixed or articulate with respect to the elongate member 104.The adapter 114 may also be a threaded coupling, a clevis, or some othertype of mechanical coupling device. Alternatively, the instrument 100may not include an adapter 114 for a mechanism, as illustrated in FIGS.4A and 4B.

In the exemplary embodiment depicted in FIG. 1C, the mechanism is asuturing head 109. The head 109 defines an opening 120 through which theneedle carrier 124 advances the needle 128. The head 109 includes acurved portion 126, the needle carrier 124, and a needle catch 122. Thecurved portion 126 defines a channel 178, which ends with the opening(or needle exit port 120). The curved portion 126 also defines anopening 176 for receiving tissue. The needle carrier 124 is disposedwithin the channel 178 in the curved portion 126. A distal portion 180of the needle carrier 124 defines a lumen 138 for holding the needle128. The exact structure and operation of the head 109 varies based onthe type of head used.

Referring to FIG. 2A, in one illustrative embodiment, the needle 128includes a tip 130 and a shaft 134 coupled to the tip 130, therebyforming a shoulder 132. The shaft 134 is coupled to a suture 136. Theneedle 128 is inserted into the lumen 138 and held by a slight frictionfit. The suture 136 extends out of the medical device 100.

In operation, a user (such as a physician or other medical personnel)first determines an appropriate shape for the elongate member 104 tosuit a specific patient need or to efficiently orient the distal portionof the medical device to reach the location of use. The shape mayinclude bends in multiple directions and/or in multiple places. The usermay bend the elongate member into the desired shape with his hands. Invarious embodiments of the invention, no tool is necessary to bend theelongate member 104. Alternatively, the user may use a fixture to createthe desired shape. The use of a fixture may enable the user torepeatedly duplicate a particular shape. During use, the elongate member104 retains the shape established by the user. The elongate member 104of the medical device 100 has enough column strength to withstandoperational forces without substantial distortion. The components of theactuator 110 are sized and their materials are selected such that theactuator 110 will not bind when the elongate member 104 is bent. Analternative actuator design is explained in detail with respect to FIG.3.

In the next step in the operation of the medical device, the userpositions the distal portion of the device at the location of use andactuates the actuator. In the illustrative embodiment of FIGS. 1A, 1B,and 1C, the medical device 100 is a suturing instrument, the distalportion of which is placed at the suturing location and actuated.Referring again to FIGS. 1B and 1C, actuation is accomplished by pushingon the button 117, which is attached to the pusher wire 111 via thewireform 103. The pusher wire 111 moves the coupling 150 along the track152 concomitantly moving the carrier wire 154, which slidably moves theneedle carrier 124 through the needle exit port 120. The user continuesto push the button 117 until the needle 128 enters the needle catch 122.The needle catch 122, as shown in FIG. 2B, includes openings 170 definedby successive ribs 172. The needle catch 122 receives the needle 128(coupled to the suture 136) through opening 170, the ribs 172 deflectslightly to allow the needle 128 to pass through. After the formedshoulder 132 has passed the ribs 172, the ribs 172 spring back to theiroriginal position defining the openings 170, and the needle 128 remainscaptured in the needle catch 122. The needle 128 and the needle catch122 shown are merely one possible type and other designs may be chosen.

Still describing the operation of an exemplary suturing instrument withrespect to FIGS. 1B and 1C, when the user releases the button 117, thespring 115 urges the button 117 proximally, moving the pusher wire 111,the coupling 150, the carrier wire 154, and the needle carrier 124proximally along with the button 117 to the retracted position. As theneedle carrier 124 moves back to the retracted position, the needle 128slides out of the lumen 138. The openings 170 (shown in FIG. 2B) arechosen to be smaller in dimension than the formed shoulder 132 (shown inFIG. 2A). This causes the needle catch 122 (shown in FIG. 1C and FIG.2B) to retain the needle 128, because the flat rear surface of theshoulder 132 prevents the needle 128 from passing back through theopening 170. When it is necessary to remove the needle 128 from theneedle catch 122, the needle 128 may be moved toward an enlarged portion174 (shown in FIG. 2B) of opening 170. The enlarged portion 174 is sizedto allow the formed shoulder 132 to pass through without resistance. Theneedle catch 122 may be constructed of thin stainless steel of hightemper, such as ANSI 301 full hard. The needle catch 122 may befabricated by way of stamping, laser machining, or chemical etching.

Preferably, the component materials of the medical device arebiocompatible. For example, components of the medical device, such asthe handle 102 and portions of the actuator 110, may be fabricated fromextruded, molded, or machined plastic material(s), such aspolypropylene, polycarbonate, or glass-filled polycarbonate. Othercomponents, for example, such as the mechanism, may be made of stainlesssteel. Other suitable materials will be apparent to those skilled in theart. Preferably, in embodiments in which the medical device is asuturing instrument, the material(s) used to form the suture are alsobiocompatible. The user selects the length, diameter, andcharacteristics of the suture to suit a particular application.

Additionally, mechanical components and operation such as thosedisclosed in U.S. Pat. Nos. 5,364,408 and 6,048,351, each of which isincorporated by reference herein in its entirety, may be employed withfeatures of the invention.

FIG. 3 is a schematic view of a portion of an alternative actuator foruse with a medical device in accordance with the invention, such as thatshown in FIG. 4A. The actuator 310 includes a wireform 303 with acontact form 333 at its proximal end, a spring 315, a spring tube 305,and a center tube 307. In one embodiment, the wireform 303 isconstructed of stainless steel. In another embodiment, the wireform 303is constructed of nitinol. The contact form 333, which is a Z form ofthe wireform 303 in some embodiments, is mechanically coupled to a shaft(not shown, but similar to the shaft 116 in FIG. 1B). The wireform 303extends longitudinally through the spring tube 305 and the center tube307 and out of the distal end 317 of the center tube 307. The springtube 305 extends longitudinally through the spring 315 and into theproximal end 327 of the center tube 307. Preferably, in comparison tothe spring 315, the center tube 307 has a thick wall. In one embodiment,the thick wall of the center tube 307 prevents the spring 315 fromentering the center tube 307. In another embodiment, the fact that thecenter tube 307 has an inner diameter that is smaller than the outerdiameter of the spring 315 prevents the spring 317 from entering thecenter tube 307. In some embodiments of the invention that incorporatethe actuator depicted in FIG. 3, the wireform 303 is attached to apusher wire (not shown, but similar to the pusher wire 111 in FIGS. 1Band 1C) by means of a weld, a crimp, a coupling, adhesive or othermeans. In such embodiments, the actuator may further include a washer360 to prevent the attachment from entering the distal end 317 of thecenter tube 307. In some embodiments in which the medical device is asuturing instrument, the pusher wire 311 is mechanically coupled to anextendable needle carrier (not shown, but similar to the needle carrier124 of FIG. 1C). In other embodiments in which the medical device is asuturing instrument, the wireform 303 is directly mechanically coupledto the extendable needle carrier.

In response to the contact form 333 being pressed, for example, by abutton (not shown, but similar to the button 117 of FIG. 1B), the spring315 compresses against the proximal end 327 of the center tube 307 andthe distal end of the spring tube 305 travels within the center tube 307toward the distal end 317 of the center tube 307. The distance oftravel, in one illustrative embodiment, is about 0.5 inch to about 1.0inch. The deflection of the wireform 303 is limited by the spring 315,the spring tube 305, and the center tube 307, as it travels toward thedistal end 317 of the center tube 307. The wireform 303 in someembodiments, or the pusher wire in other embodiments, actuates themechanism relative to the elongate member. For example, in someembodiments of the medical device as a suturing instrument, such asdescribed with respect to FIGS. 1B and 1C, the wireform 303 advances aneedle via the needle carrier to the needle catch.

The components of the actuator 310 are sized and their materials areselected such that the actuator 310 will not bind when the elongatemember (not shown, but similar to the elongate member 104 of FIGS. 1Band 1C) is bent. The center tube 307, the spring tube 305, the spring315, and the wireform 303 are flexible components. When the elongatemember is bent, the components inside bend with it. The outer diameterof the center tube 307 is preferred to be close to the inner diameter ofthe elongate member to prevent kinking In some embodiments, the bentelongate member holds the center tube 307 stationary. In someembodiments, the clearance between the center tube 307 and the springtube 305 is ample to allow the spring tube 305 to travel even when thecenter tube 307 is bent. The outer diameter of the spring 315, in someembodiments, is much smaller than the inner diameter of the elongatemember 304 thereby allowing the spring 315 to move when the elongatemember 304 is bent. The spring 315 is also located in a position withinthe elongate member where the elongate member is less likely to be bent.

In accordance with another illustrative aspect of the invention, FIG. 4Adepicts a medical device 400 including an elongate member 404, amechanism, and an actuator 410. In the particular illustrativeembodiment of FIG. 4A, the medical device 400 is a suturing instrumentand the mechanism is a needle carrier 424. The elongate member 404includes a distal portion 406. In the specific embodiment depicted inFIG. 4A, the elongate member 404 also defines an opening 420. Like theelongate member 104 depicted in FIG. 1A, the elongate member 404depicted in FIG. 4A is capable of being bent into a shape and ofretaining the shape during use. The mechanism is disposed at the distalportion 406 of the elongate member 404. The needle carrier mechanism424, in particular, is designed to hold a needle 428. The actuator 410is at least partially disposed within the elongate member 404 andcoupled to the mechanism for actuating the mechanism relative to theelongate member 404. In the specific embodiment depicted in FIG. 4A, theactuator 410 is coupled to the needle carrier mechanism 424 foradvancing the needle 428 out of the opening 420.

FIG. 4B is a view of the medical device 400 of FIG. 4A bent into a shapefor a particular application. The needle 428 in FIG. 4B is partiallyadvanced out of the opening 420 by the needle carrier mechanism 424. Theshape of the elongate member 404 in FIG. 4B features a first bend 450and a second bend 470. Although the first bend 450 and the second bend470 are both smooth, shallow curves, the first bend 450 is sharper thanthe second bend 470. A section 460, between the first bend 450 and thesecond bend 470, is generally straight. As shown in FIG. 4B, the outersurface of the distal portion 406 of the elongate member 404 has beenscored in a spiral pattern. The scoring may be done to increase thebendability of the distal portion 406 of the elongate member 404.

FIGS. 5A and 5B depict an elongate member 504, such as described withrespect to FIGS. 1A-1C and FIGS. 4A-4B, bent into a first shape 550 anda second shape 570. The elongate member depicted in FIGS. 5A and 5B isgenerally tubular and has a proximal end 508 and a distal end 506. Thefirst shape 550 includes a first bend 552, a second bend 554, and athird bend 556. The first bend 552 forms an obtuse angle in the elongatemember 504. The first bend 552 is also sharper than the second bend 554,which is sharper than the third bend 556. The third bend 556 may best bedescribed as a gentle curve. The first bend 552, second bend 554, andthird bend 556 are all coplanar. The second shape 570 includes a firstbend 572, a second bend 574, and a third bend 576. The second bend 574is sharper than the first bend 572, which is sharper than the third bend576. The second bend 574 forms an angle less than 90.degree. in theelongate member 504. Each bend 572, 574, 576 in the second shape 570 hasa completely different orientation than the other bends. The proximalportion 508 of the elongate member 504 in the second shape 570 iscoplanar with a section 510 of the elongate member 504 between the firstbend 572 and the second bend 574. However, a section 512 of the elongatemember 504 between the second bend 574 and the third bend 576 does notfall within the same plane as the proximal portion 508, because thesecond bend 574 is rotated out of the plane of the first bend 572.Similarly, a section 514 of the elongate member 504 on the opposite sideof the third bend 576 with respect to section 512 does not fall withinthe same plane as section 510 because the third bend 576 is rotated outof the plane of the second bend 574.

Portions of the elongate member 504 may remain straight for a particularuse. For example, the proximal end of the elongate member 504 may remainunbent for a particular use as depicted in FIGS. 5A and 5B. In fact, theelongate member 504 need not be bent at all for a particularapplication. When the elongate member 504 is bent for a particularapplication, it need not been bent in the same location or locationsthat it has previously been bent. The elongate member 504 may have moreor less than three bends for a particular application. Further, allbends may be similarly oriented for a particular application. Forexample, a user may want the elongate member to be shaped into an arc.

In various embodiments of the foregoing aspects of the invention, theelongate member 504 depicted in FIGS. 5A and 5B may have a variablestiffness along its length. The proximal end 508 may be stiffer than thedistal end 506 of the elongate member 504, because it is more likelythat the distal end 506 will require bending. The diameter of theelongate member 504 may vary along its longitudinal axis. Having asmaller diameter at, at least one point along the longitudinal axis ofthe elongate member 504 may allow the elongate member 504 to bend moreeasily at that point. The elongate member 504 may have a smallerdiameter at its distal end 506 than at its proximal end 508. The smallerdiameter at the distal end 506 of the elongate member 504 may allow theelongate member 504 to be used in smaller openings in the human body. Invarious embodiments of the foregoing aspects of the invention, theelongate member 504 may have a non-uniform wall-thickness. Thenon-uniform wall-thickness, in some embodiments, is achieved by materialselection. The wall thickness, in other embodiments, is thinned atvarious locations along the length of the elongate member 504 to makethe elongate member 504 easier to bend where the wall is thinner. Thenon-uniform wall thickness may be at least partially due to etching. Thenon-uniform wall-thickness may be at least partially due to scoring.Etching or scoring may be done in lines parallel or transverse to thelongitudinal axis of the elongate member 504, in a spiral pattern, or inanother pattern. The inner surface of the elongate member 504, the outersurface of the elongate member 504, or both surfaces may be etched orscored. Spiral scoring, for example, may allow the elongate member 504to bend more easily without kinking Other means of and approaches tomodifying wall thickness will be obvious to those of skill in the art.

In various embodiments of the invention, the elongate member 504depicted in FIGS. 5A and 5B may have a variety of surfacecharacteristics. For example, one embodiment of the elongate member 504has an entirely smooth outer surface. Another embodiment may have anouter surface that is at least partly rough. Scoring or etching thesurface of the elongate member 504 may, for example, cause theroughness. Roughness may be undesirable due to the possibility ofinteraction with human tissue during use or due to a greater difficultyin cleaning the instrument. Roughness on the outer surface of theelongate member 504 may be avoided, where necessary, by thinning thewall thickness from the inner surface of the elongate member 504.Alternatively, covering at least some of the rough surface areas with asmooth material may alleviate any potential problems due to roughness onthe outer surface of the elongate member 504.

An elongate member 504, such as those depicted in FIGS. 5A and 5B andused in medical devices exemplified by FIGS. 1A-1C and FIGS. 4A-4B, canhave essentially any cross-sectional shape. Such cross-sectional shapesinclude polygonal, arcuate, or combinations of polygonal and arcuateelements. In the present application, the term polygonal is used todenote any shape including at least two line segments, such asrectangles, trapezoids, and triangles. Examples of arcuate shapesinclude circular and elliptical. FIGS. 5A and 5B specifically depict anelongate member 504 with a circular cross-section and generallycylindrical shape according to one embodiment of the invention. Theelongate member 504 may, for example, have a tubular shape.

In various embodiments of the foregoing aspects of the invention, theelongate member is made of metals, alloys, or plastics or a combinationthereof. Metals that can be used to form the elongate member include:nickel, copper, stainless steel, cobalt, vanadium, chromium, iron, andsuperelastic metallic alloys. Plastics that can be used to form theelongate member include synthetic plastics, polyurethanes, polyesterelastomers, and nylons. In embodiments in which the elongate memberitself is not necessarily made of a biocompatible material, the externalsurface of the elongate member may be at least partially covered with abiocompatible material. In embodiments with a particularly long elongatemember, for example, the proximal portion of the elongate member is madeof or covered with a biocompatible material. The entire external surfaceof the elongate member of other embodiments may be made of or coveredwith a biocompatible material. The biocompatible material may bestainless steel, polyvinyl chloride, polytetraflouroethylene, expandedpolytetraflouroethylene, ethylene-tetrafluoroethylene, silicone, orother suitable material. In some embodiments, the external surface ofthe elongate member is at least partly plated or spray coated with abiocompatible material. In other embodiments, other techniques, such asheat-shrinking, are used to apply the biocompatible material. Othermaterials and application techniques can be used.

The elongate member 504 described above can be combined with a varietyof actuators and mechanisms to form a variety of medical devices. Suchmedical devices include, but are not limited to, imaging devices,stapling devices, biopsy devices, injection devices, cutting devices,and capturing devices, as used in endoscopic procedures.

Other embodiments incorporating the concepts disclosed herein are withinthe spirit and scope of the invention. The described embodiments are tobe considered in all respects as only illustrative and not restrictive.

1. A medical device comprising: a handle; an elongate member extendingfrom the handle and capable of being bent into a shape by a user alongits entire length and having variable stiffness, the elongate memberhaving a proximal portion and a distal portion, the elongate membercomprising a first tube; and an actuator at least partially disposedwithin the proximal portion of the elongate member and comprisingmechanical linkage that extends longitudinally through the elongatemember to the distal portion, the actuator comprising a spring, a secondtube, and a third tube, each capable of being bent when the elongatemember is bent, the second tube disposed adjacent to a distal end of thespring, the third tube at least partially longitudinally extendedthrough each of the spring and the second tube, the third tube spacedapart from the inner surface of the second tube when unbent andslideable within the second tube when the second tube is bent.
 2. Themedical device of claim 1, wherein the distal portion of the elongatemember has increased bendability.
 3. The medical device of claim 1,wherein the elongate body member is capable of retaining the shapeduring use.
 4. The medical device of claim 1, further comprising aneedle carrier holding a needle, the needle carrier is mechanicallycoupled to the actuator for advancing the needle out of an openingdefined by the distal portion of the elongate member.
 5. The medicaldevice of claim 1, further comprising a needle catch defining at leastone opening disposed on the elongate member.
 6. The medical device ofclaim 4, wherein the needle catch is configured to receive the needlethrough the at least one opening and retain the needle after the needlecarrier is retracted.
 7. The medical device of claim 1, wherein thefirst tube is at least partially spiral cut.
 8. The medical device ofclaim 1, wherein the elongate member comprises a material selected fromthe group consisting of metals, alloys, and plastics.
 9. The medicaldevice of claim 7, wherein the metal is selected from nickel, copper,stainless steel, cobalt, vanadium, chromium, iron, and super elasticmetallic alloys.
 10. The medical device of claim 7, wherein the plasticsare selected from synthetic plastics, polyurethanes, polyesterelastomers, and nylons.
 11. The medical device of claim 1, wherein anexternal surface of the elongate member is at least partially coveredwith a biocompatible material.
 12. The medical device of claim 1,wherein the elongate member is capable of bending in one or moredirections.
 13. A medical device comprising: a handle; an elongatemember extending from the handle and capable of being bent into a shapeby a user along its entire length and having variable stiffness, theelongate member having a proximal portion and a distal portion, theelongate member comprising a first tube; an actuator at least partiallydisposed within the proximal portion of the elongate member andcomprising mechanical linkage that extends longitudinally through theelongate member to the distal portion, the actuator comprising a spring,a second tube, a third tube, and a wireform, each capable of being bentwhen the elongate member is bent, the second tube disposed adjacent adistal end of the spring, the third tube at least partiallylongitudinally extended through each of the spring and the second tube,the third tube spaced apart from the inner surface of the second tubewhen unbent and slideable within the second tube when the second tube isbent, the wireform at least extending longitudinally within the secondtube and third tube and out of a distal end of the second tube; thewireform mechanically coupled to an extendable needle carrier foradvancing the needle carrier out of an opening defined by the distal endof the elongate body, the needle carrier holding a needle.
 14. Themedical device of claim 13, wherein the distal portion of the elongatemember has increased bendability.
 15. The medical device of claim 13,wherein the elongate body member is capable of retaining the shapeduring use.
 16. The medical device of claim 13, further comprising aneedle catch defining at least one opening disposed on the elongatemember.
 17. The medical device of claim 16, wherein the needle catch isconfigured to receive the needle through the at least one opening andretain the needle after the needle carrier is retracted.
 18. The medicaldevice of claim 13, wherein the first tube is at least partially spiralcut.
 19. The medical device of claim 13, wherein the elongate membercomprises a material selected from the group consisting of metals,alloys, and plastics.
 20. The medical device of claim 13, wherein themetal is selected from nickel, copper, stainless steel, cobalt,vanadium, chromium, iron, and super elastic metallic alloys.
 21. Themedical device of claim 13, wherein the plastics are selected fromsynthetic plastics, polyurethanes, polyester elastomers, and nylons. 22.The medical device of claim 13, wherein the elongate member is capableof bending in one or more directions.